Modern times, fancy anniversaries — it's as if we wouldn't trust ourselves with remembering a person or an event unless we had a specific date in the calendar reserved for that.
Anniversaries arrive with a predetermined mood: grief, gratitude, sadness, anger, or a combination of all of the above and more. The mood: we choose it instinctively, responding to how we feel, and when our gut feeling clashes with the opinions of others, we get upset. This is why controversy always clouds national holidays — what is it that we are celebrating and what is the right way to mark the day.
But there are controversies and controversies. Historic dates have been on the calendar long enough for most communities to get tired of arguing about their meaning, and as often as not we agree to disagree in an amiable fashion. ("What are you doing for XYZ Day?" "XYZ Day? Nothing." "Hmm. Strange. We always have a picnic.").